Earlier this month a jailbreak for iOS devices launched called Evasi0n. The jailbreak proved to be incredibly popular racking up 800,000 downloads in the first six hours it was available – after all, this was the first “untethered” jailbreak available for the iPhone 5.

However, Forbes reports that Apple is currently beta testing an update for iOS that crushes the Evasi0n jailbreak.

According to David Wang, one of the creators of the jailbreak, an analysis of the 6.1.3 Beta 2 update determined that the update patches at least one of the five iOS flaws that the jailbreak exploits. Specifically, the new iOS update patches a flaw in the time zone settings for the operating system.

“If one of the vulnerabilities doesn’t work, evasi0n doesn’t work,” he says. “We could replace that part with a different vulnerability, but [Apple] will probably fix most if not all of the bugs we’ve used when 6.1.3 comes out.”

Wang expects that could be as long as another month before the 6.1.3 update is available to the public, so for now users of his jailbreak can continue using it with no problems. And considering that any 6.1.x update is unlikely to add any new functionality, most people will just stick with the 6.1.2 Evasi0n jailbreak permanently.